Soybean variety XB02C03

ABSTRACT

According to the invention, there is provided a novel soybean variety, designated XB02C03. This invention thus relates to the seeds of soybean variety XB02C03, to the plants of soybean XB02C03 to plant parts of soybean variety XB02C03 and to methods for producing a soybean plant produced by crossing soybean variety XB02C03 with another soybean plant, using XB02C03 as either the male or the female parent. This invention also relates to methods for producing a soybean plant containing in its genetic material one or more transgenes and to the transgenic soybean plants and plant parts produced by those methods. This invention also relates to soybean varieties or breeding varieties and plant parts derived from soybean variety XB02C03, to methods for producing other soybean varieties, lines or plant parts derived from soybean variety XB02C03 and to the soybean plants, varieties, and their parts derived from use of those methods. This invention further relates to soybean seeds, plants, and plant parts produced by crossing the soybean variety XB02C03 with another soybean variety preferably as part of a breeding program.

FIELD OF INVENTION

This invention is in the field of soybean breeding, specificallyrelating to a soybean variety designated XB02C03.

BACKGROUND OF INVENTION

The present invention relates to a new and distinctive soybean variety,designated XB02C03 which has been the result of years of carefulbreeding and selection as part of a soybean breeding program. There arenumerous steps in the development of any novel, desirable plantgermplasm. Plant breeding begins with the analysis and definition ofproblems and weaknesses of the current germplasm, the establishment ofprogram goals, and the definition of specific breeding objectives. Thenext step is selection of germplasm that possess the traits to meet theprogram goals. The goal is to combine in a single variety an improvedcombination of desirable traits from the parental germplasm. Theseimportant traits may include higher seed yield, resistance to diseasesand insects, tolerance to drought and heat, and better agronomicqualities.

These processes, which lead to the final step of marketing anddistribution, can take from six to twelve years from the time the firstcross is made. Therefore, development of new varieties is atime-consuming process that requires precise forward planning, efficientuse of resources, and a minimum of changes in direction.

Soybean (Glycine max), is an important and valuable field crop. Thus, acontinuing goal of soybean breeders is to develop stable, high yieldingsoybean varieties that are agronomically sound. The reasons for thisgoal are obviously to maximize the amount of grain produced on the landused and to supply food for both animals and humans. To accomplish thisgoal, the soybean breeder must select and develop soybean plants thathave the traits that result in superior varieties.

Pioneer soybean research staff creates over 500,000 potential newvarieties each year. Of those new varieties, less than 50 and morecommonly less than 25 are actually selected for commercial use.

The soybean is the world's leading source of vegetable oil and proteinmeal. The oil extracted from soybeans is used for cooking oil,margarine, and salad dressings. Soybean oil is composed of saturated,monounsaturated and polyunsaturated fatty acids. It has a typicalcomposition of 11% palmitic, 4% stearic, 25% oleic, 50% linoleic and 9%linolenic fatty acid content (“Economic Implications of Modified SoybeanTraits Summary Report”, Iowa Soybean Promotion Board & American SoybeanAssociation Special Report 92S, May 1990). Changes in fatty acidcomposition for improved oxidative stability and nutrition areconstantly sought after. Industrial uses of soybean oil which issubjected to further processing include ingredients for paints,plastics, fibers, detergents, cosmetics, and lubricants. Soybean oil maybe split, inter-esterified, sulfurized, epoxidized, polymerized,ethoxylated, or cleaved. Designing and producing soybean oil derivativeswith improved functionality, oliochemistry, is a rapidly growing field.The typical mixture of triglycerides is usually split and separated intopure fatty acids, which are then combined with petroleum-derivedalcohols or acids, nitrogen, sulfonates, chlorine, or with fattyalcohols derived from fats and oils.

Soybean is also used as a food source for both animals and humans.Soybean is widely used as a source of protein for animal feeds forpoultry, swine and cattle. During processing of whole soybeans, thefibrous hull is removed and the oil is extracted. The remaining soybeanmeal is a combination of carbohydrates and approximately 50% protein.

For human consumption soybean meal is made into soybean flour which isprocessed to protein concentrates used for meat extenders or specialtypet foods. Production of edible protein ingredients from soybean offersa healthy, less expensive replacement for animal protein in meats aswell as dairy-type products.

SUMMARY OF INVENTION

According to the invention, there is provided a novel soybean variety,designated XB02C03. This invention thus relates to the seeds of soybeanvariety XB02C03, to the plants of soybean XB02C03 to plant parts ofsoybean variety XB02C03 and to methods for producing a soybean plantproduced by crossing soybean variety XB02C03 with another soybean plant,using XB02C03 as either the male or the female parent. This inventionalso relates to methods for producing a soybean plant containing in itsgenetic material one or more transgenes and to the transgenic soybeanplants and plant parts produced by those methods. This invention alsorelates to soybean varieties or breeding varieties and plant partsderived from soybean variety XB02C03, to methods for producing othersoybean varieties, lines or plant parts derived from soybean varietyXB02C03 and to the soybean plants, varieties, and their parts derivedfrom use of those methods. This invention further relates to soybeanseeds, plants, and plant parts produced by crossing the soybean varietyXB02C03 with another soybean variety preferably as part of a breedingprogram.

Definitions

Certain definitions used in the specification are provided below. Alsoin the examples which follow, a number of terms are used. In order toprovide a clear and consistent understanding of the specification andclaims, including the scope to be given such terms, the followingdefinitions are provided:

ALLELE=any of one or more alternative forms of a genetic sequence. In adiploid cell or organism, the two alleles of a given sequence occupycorresponding loci on a pair of homologous chromosomes.

BACKCROSSING=Process in which a breeder crosses a progeny variety backto one of the parental genotypes one or more times.

BREEDING=The genetic manipulation of living organisms.

BU/A=Bushels per Acre. The seed yield in bushels/acre is the actualyield of the grain at harvest.

BSR=Brown Stem Rot Tolerance. This is a visual disease score from 1 to 9comparing all genotypes in a given test. The score is based on leafsymptoms of yellowing and necrosis caused by brown stem rot. A score of9 indicates no symptoms. Visual scores range down to a score of 1 whichindicates severe symptoms of leaf yellowing and necrosis. In the tablesprovided herein, susceptible means a score of 1-3 and resistant means ascore of 6-9.

CNKR=Stem Canker Tolerance. This is a visual disease score from 1 to 9comparing all genotypes in a given test. The score is based uponpremature plant death. A score of 9 indicates no symptoms, whereas ascore of 1 indicates the lo entire experimental unit died very early.

COTYLEDON=A cotyledon is a type of seed leaf. The cotyledon contains thefood storage tissues of the seed.

ELITE VARIETY=A variety that is sufficiently homozygous and homogeneousto be used for commercial grain production. An elite variety may also beused in is further breeding.

EMBRYO=The embryo is the small plant contained within a mature seed.

EMGSC=Emergence Score. The percentage of emerged plants in a plotrespective to the number of seeds planted.

F3=This symbol denotes a generation resulting from the selfing of the F2generation along with selection for type and rogueing of off-types. The“F” number is a term commonly used in genetics, and designates thenumber of the filial generation. The “F3” generation denotes theoffspring resulting from the selfing or self mating of members of thegeneration having the next lower “F” number, viz. the F2 generation.

FEC=Iron-deficiency Chlorosis. Plants are scored 1 to 9 based on visualobservations. A score of 1 indicates the plants are dead or dying fromiron-deficiency chlorosis, a score of 5 means plants have intermediatehealth with some leaf yellowing and a score of 9 means no stunting ofthe plants or yellowing of the leaves. Plots are usually scored in midJuly.

FECL=Iron-deficiency Chlorosis. Plants are scored 1 to 9 based on visualobservations. A score of 1 indicates the plants are dead or dying fromiron-deficiency chlorosis, a score of 5 means plants have intermediatehealth with some leaf yellowing and a score of 9 means no stunting ofthe plants or yellowing of the leaves. Plots are scored around midAugust.

FEY=Frogeye Tolerance. This is a visual disease score from 1 to 9comparing all genotypes in a given test. The score is based upon leaflesions. A score of 9 indicates no lesions, whereas a score of 1indicates severe leaf necrosis.

G/C COUNT=Seed weight as measured in grams per 100 seeds.

GENOTYPE=Refers to the genetic constitution of a cell or organism.

HABIT=This refers to the physical appearance of a plant. It can bedeterminate, semi-determinate, intermediate, or indeterminate. Insoybeans, indeterminate varieties are those in which stem growth is notlimited by formation of a reproductive structure (i.e., flowers, podsand seeds) and hence growth continues throughout flowering and duringpart of pod filling. The main stem will develop and set pods over aprolonged period under favorable conditions. In soybeans, determinatevarieties are those in which stem growth ceases at flowering time. Mostflowers develop simultaneously, and most pods fill at approximately thesame time. The terms semi-determinate and intermediate are also used todescribe plant habit and are defined in Bernard, R. L. 1972. “Two genesaffecting stem termination in soybeans.” Crop Science 12:235-239;Woodworth, C. M. 1932. “Genetics and breeding in the improvement of thesoybean.” Bull. Agric. Exp. Stn. (Illinois) 384:297-404; Woodworth, C.M. 1933. “Genetics of the soybean.” J. Am. Soc. Agron. 25:36-51.

HGT=Plant Height. Plant height is taken from the top of the soil to toppod of the plant and is measured in inches.

HILUM=This refers to the scar left on the seed which marks the placewhere the seed was attached to the pod prior to it (the seed) beingharvested.

HYPL=Hypocotyl Elongation. This score indicates the ability of the seedto emerge when planted 3″ deep in sand pots and with a controlledtemperature of 25° C. The number of plants that emerge each day arecounted. Based on this data, each genotype is given a 1 to 9 score basedon its rate of emergence and percent of emergence. A score of 9indicates an excellent rate and percent of emergence, an intermediatescore of 5 indicates average ratings and a 1 score indicates a very poorrate and percent of emergence.

HYPOCOTYL=A hypocotyl is the portion of an embryo or seedling betweenthe cotyledons and the root. Therefore, it can be considered atransition zone between shoot and root.

LDGSEV=Lodging Resistance. Lodging is rated on a scale of 1 to 9. Ascore of 9 indicates erect plants. A score of 5 indicates plants areleaning at a 45° angle in relation to the ground and a score of 1indicates plants are laying on the ground.

LEAFLETS=These are part of the plant shoot, and they manufacture foodfor the plant by the process of photosynthesis.

LINKAGE=Refers to a phenomenon wherein alleles on the same chromosometend to segregate together more often than expected by chance if theirtransmission was independent.

LINKAGE DISEQUILIBRIUM=Refers to a phenomenon wherein alleles tend toremain together in linkage groups when segregating from parents tooffspring, with a greater frequency than expected from their individualfrequencies.

LLE=Linoleic Acid Percent. Linoleic acid is one of the five mostabundant fatty acids in soybean seeds. It is measured by gaschromatography and is reported as a percent of the total oil content.

LLN=Linolenic Acid Percent. Linolenic acid is one of the five mostabundant fatty acids in soybean seeds. It is measured by gaschromatography and is reported as a percent of the total oil content.

MAT ABS=Absolute Maturity. This term is defined as the length of timefrom planting to complete physiological development (maturity). Theperiod from planting until maturity is reached is measured in days,usually in comparison to one or more standard varieties. Plants areconsidered mature when 95% of the pods have reached their mature color.

MATURITY GROUP=This refers to an agreed-on industry division of groupsof varieties, based on the zones in which they are adapted primarilyaccording to day length or latitude. They consist of very long daylength varieties (Groups 000, 00, 0), and extend to very short daylength varieties (Groups VII, VIII, IX, X).

OIL=Oil Percent. Soybean seeds contain a considerable amount of oil. Oilis measured by NIR spectrophotometry, and is reported on an as ispercentage basis.

OLC=Oleic Acid Percent. Oleic acid is one of the five most abundantfatty acids in soybean seeds. It is measured by gas chromatography andis reported as a percent of the total oil content.

PEDIGREE DISTANCE=Relationship among generations based on theirancestral links as evidenced in pedigrees. May be measured by thedistance of the pedigree from a given starting point in the ancestry.

PRT=Phytophthora megasperma var sojae response. PRT or PRTLAB is avisual disease score from 1 to 9 comparing all genotypes in a giventest, including known resistant and susceptible checks for use asreferences in scoring. The score is based upon assessing soybeanseedlings for damage from hypocotyl inoculation with a race specificculture. A score of 9 indicates that the seedling is as viable as theresistant check, and a score of 1 indicates that the seedling is asdamaged as the susceptible check. In the tables provided herein,susceptible means a score of 1-3 and resistant means a score of 6-9.When response is shown with reference to a particular phytophthora race(PMG), such response is determined by a specific allele conferring racespecific resistance. Individual alleles as individual loci can bedetermined by marker analysis and/or bioassay.

PLM=Palmitic Acid Percent. Palmitic acid is one of the five mostabundant fatty acids in soybean seeds. It is measured by gaschromatography and is reported as a percent of the total oil content.

POD=This refers to the fruit of a soybean plant. It consists of the hullor shell (pericarp) and the soybean seeds.

PRMMAT=Predicted Relative Maturity. Soybean maturities are divided intorelative maturity groups. In the United States the most common maturitygroups are 00 through VIII. Within maturity groups 00 through V aresub-groups. A sub-group is a tenth of a relative maturity group. Withinnarrow comparisons, the difference of a tenth of a relative maturitygroup equates very roughly to a day difference in maturity at harvest.

PRO=Protein Percent. Soybean seeds contain a considerable amount ofprotein. Protein is generally measured by NIR spectrophotometry, and isreported on an as is percentage basis.

PUBESCENCE=This refers to a covering of very fine hairs closely arrangedon the leaves, stems and pods of the soybean plant.

RKI=Root-knot Nematode, Southern. This is a visual disease score from 1to 9 comparing all genotypes in a given test. The score is based upondigging plants to visually score the roots for presence or absence ofgalling. A score of 9 indicates that there is no galling of the roots, ascore of 1 indicates large severe galling cover most of the root systemwhich results in pre-mature death from decomposing of the root system.

RKA=Root-knot Nematode, Peanut. This is a visual disease score from 1 to9 comparing all genotypes in a given test. The score is based upondigging plants to look at the roots for presence or absence of galling.A score of 9 indicates that there is no galling of the roots, a score of1 indicates large severe galling cover most of the root system whichresults in pre-mature death from decomposing of the root system.

SCN=Soybean Cyst Nematode Response. This is a visual disease score from1 to 9 comparing all genotypes in a given test, including knownresistant and susceptible checks for use as references in scoring. Thescore is based upon assessing soybean seedling roots for the number ofcysts. A score of 9 indicates that the number of cysts on the roots ofthe experimental variety is equal to or less than 7% of the number ofcysts on the roots of the susceptible check, and a score of 1 indicatesthat the number of cysts on the roots of the experimental variety isequal to or greater than the number of cysts on the roots of thesusceptible check. In the tables provided herein, susceptible means ascore of 1-3 and resistant means a score of 6-9.

SD VIG=Seedling Vigor. The score is based on the speed of emergence ofthe plants within a plot relative to other plots within an experiment. Ascore of 9 indicates that 90% of plants growing have expanded firstleaves. A score of 1 indicates no plants have expanded first leaves.

SDS=Sudden Death Syndrome. Tolerance to Sudden Death Syndrome is ratedon a scale of 1 to 9, with a score of 1 being very susceptible rangingup to a score of 9 being tolerant.

S/LB=Seeds per Pound. Soybean seeds vary in seed size, therefore, thenumber of seeds required to make up one pound also varies. This affectsthe pounds of seed required to plant a given area, and can also impactend uses.

SHATTR=Shattering. This refers to the amount of pod dehiscence prior toharvest. Pod dehiscence involves seeds falling from the pods to thesoil. This is a visual score from 1 to 9 comparing all genotypes withina given test. A score of 9 means pods have not opened and no seeds havefallen out. A score of 5 indicates approximately 50% of the pods haveopened, with seeds falling to the ground and a score of 1 indicates 100%of the pods are opened.

SHOOTS=These are a portion of the body of the plant. They consist ofstems, petioles and leaves.

STC=Stearic Acid Percent. Stearic acid is one of the five most abundantfatty acids in soybean seeds. It is measured by gas chromatography andis reported as a percent of the total oil content.

WH MD=White Mold Tolerance. This is a visual disease score from 1 to 9comparing all genotypes in a given test. The score is based uponobservations of mycelial growth and death of plants. A score of 9indicates no symptoms. Visual scores of 1 indicate complete death of theexperimental unit.

YIELD BUIA=Yield (Bushels/Acre). Yield of the grain at harvest inbushels per acre adjusted to 13.5% moisture, with a bushel being equalto 60 pounds.

Definitions for Area of Adaptability

When referring to area of adaptability, such term is used to describethe location with the environmental conditions that would be well suitedfor this soybean variety. Area of adaptability is based on a number offactors, for example: days to maturity, insect resistance, diseaseresistance, and drought resistance. Area of adaptability does notindicate that the soybean variety will grow in every location within thearea of adaptability or that it will not grow outside the area.

Midwest: Iowa and Missouri

Heartland: Illinois and the western half of Indiana

Plains: ⅔ of the eastern parts of South Dakota and Nebraska

North Central: Minnesota, Wisconsin, the Upper Peninsula of Michigan,and the eastern half of North Dakota

Mideast: Michigan, Ohio, and the eastern half of Indiana

Eastern: Pennsylvania, Delaware, Maryland, Rhode Island, New Jersey,Connecticut, Massachusetts, New York, Vermont, and Maine

Southern: Virginia, West Virginia, Tennessee, Kentucky, Arkansas, NorthCarolina, South Carolina, Georgia, Florida, Alabama, Mississippi, andLouisiana

Western: Texas, Kansas, Colorado, Oklahoma, New Mexico, Arizona, Utah,Nevada, California, Washington, Oregon, Montana, Idaho, Wyoming, thewestern half of North Dakota, and the western ⅓ South Dakota andNebraska

PMG infested soils: soils containing Phytophthora megasperma

Narrow rows: 7″ and 15″ row spacing

High yield environments: areas which lack normal stress for example theyhave sufficient rainfall, water drainage, low disease pressure, and lowweed pressure

Tough environments: areas which have stress challenges, opposite of ahigh yield environment

DETAILED DESCRIPTION OF INVENTION

The variety of the invention has shown uniformity and stability for alltraits, as described in the following variety description information.It has been self-pollinated a sufficient number of generations, withcareful attention to uniformity of plant type to ensure homozygosity andphenotypic stability. The variety has been increased with continuedobservation for uniformity. No variant traits have been observed or areexpected in XB02C03, as described in Table 1 (Variety DescriptionInformation).

Soybean variety XB02C03 is a purple flowered soybean variety with tawnycolored plant pubescence and tan colored hila. Soybean variety XB02C03is in the relative maturity group 0, sub-group 2, and is particularlyadapted to Canada and the North Central and Western areas of the UnitedStates. This variety does well in Phytophthora infected soils. Thevariety XB02C03 displays Brown Stem Rot resistance and a substantialdegree of glyphosate resistance.

Soybean variety XB02C03, being substantially homozygous, can bereproduced by planting seeds of the variety, growing the resultingsoybean plants under self-pollinating or sib-pollinating conditions, andharvesting the resulting seed, using techniques familiar to theagricultural arts.

TABLE 1 Variety Description Information XB02C03 A. Mature SeedCharacteristics: Seed Coat Color: yellow Seed Size (grams per 100seeds): 14 Hilum Color: tan Seed Shape: spherical-flattened Seed CoatLuster: dull B. Leaf: Leaflet Shape: ovate C. Plant Characteristics:Flower Color: purple Pod Color: brown Cotyledon Color: yellow HypocotylColor: dark purple Plant Pubescence Color: tawny Plant Habit:indeterminate Maturity Group: 0 Maturity Sub-Group: 2 D. Fungal Diseases(S = susceptible R = resistant) Phytophthora Root Rot Race 3: R Race 7:R Race 4: R Race 25: S Brown Stem Rot (Cephalosporium gregatum):Resistant E. Glyphosate: Resistant

Publications useful as references in interpreting Table 1 include:

Caldwell, B. E. ed. 1973. “Soybeans: Improvement, Production, and Uses”Amer. Soc. Agron. Monograph No. 16;

Buttery, B. R., and R. I. Buzzell 1968. “Peroxidase Activity in Seed ofSoybean Varieties” Crop Sci. 8: 722-725;

Hymowitz, T. 1973. “Electrophoretic analysis of SBTI-A2 in the USDASoybean Germplasm Collection” Crop Sci., 13: 420-421;

Payne R. C., and L. F. Morris, 1976. “Differentiation of SoybeanVarieties by Seedling Pigmentation Patterns” J. Seed. Technol. 1: 1-19.The disclosures of which are each incorporated by reference in theirentirety.

Performance Examples of XB02C03

In the examples that follow in Table 2, the traits and characteristicsof soybean variety XB02C03 are given in paired comparisons with the fourPioneer varieties 90B11 (Table 2A), 90B51 (Table 2B), 90B73 (Table 2C)and 90B74 (Table 2D).

TABLE 2A VARIETY COMPARISON DATA FOR XB02C03 YIELD bu/a MATABS LDGSEVHGT in Variety1 Variety2 Statistic 60# ABS count ABS score ABS ABSXB02C03 90B11 Mean1 42.1 118.6 7.3 30 XB02C03 90B11 Mean2 37.2 116.8 5.730 XB02C03 90B11 #Locs 23 16 6 7 XB02C03 90B11 #Reps 45 30 11 13 XB02C0390B11 #Years 3 3 3 3 XB02C03 90B11 Diff 4.9 1.7 1.7 −1 XB02C03 90B11Prob 0.0007 0.049 0.0199 0.6564 FEC BSR PRTLAB EMGSC Variety1 Variety2Statistic score ABS score ABS score ABS score ABS XB02C03 90B11 Mean16.2 7 5.7 5.9 XB02C03 90B11 Mean2 5.3 4.3 5.7 6.6 XB02C03 90B11 #Locs 71 2 3 XB02C03 90B11 #Reps 19 3 6 9 XB02C03 90B11 #Years 3 1 2 2 XB02C0390B11 Diff 0.9 2.7 0 −0.7 XB02C03 90B11 Prob 0.0068 1 0.5973 SDVIG OILTPROT G/C Variety1 Variety2 Statistic score ABS pct ABS pct ABS count ABSXB02C03 90B11 Mean1 6 21.1 40.4 15 XB02C03 90B11 Mean2 7.3 20.4 41.214.3 XB02C03 90B11 #Locs 3 6 6 6 XB02C03 90B11 #Reps 9 6 6 6 XB02C0390B11 #Years 2 2 2 2 XB02C03 90B11 Diff −1.3 0.7 −0.8 0.7 XB02C03 90B11Prob 0.0742 0.0213 0.1333 0.2579

TABLE 2B VARIETY COMPARISON DATA FOR XB02C03 YIELD bu/a MATABS LDGSEVHGT in Variety1 Variety2 Statistic 60# ABS count ABS score ABS ABSXB02C03 90B51 Mean1 40.6 116.5 6.7 31 XB02C03 90B51 Mean2 42.4 118.3 6.233 XB02C03 90B51 #Locs 16 11 3 4 XB02C03 90B51 #Reps 32 21 6 8 XB02C0390B51 #Years 2 2 2 2 XB02C03 90B51 Diff −1.7 −1.8 0.5 2 XB02C03 90B51Prob 0.2825 0.3822 0.4226 0.2939 FEC BSR PRTLAB EMGSC Variety1 Variety2Statistic score ABS score ABS score ABS score ABS XB02C03 90B51 Mean16.5 7 5.7 5.9 XB02C03 90B51 Mean2 7 3.7 5.2 5.3 XB02C03 90B51 #Locs 5 12 3 XB02C03 90B51 #Reps 14 3 6 9 XB02C03 90B51 #Years 2 1 2 2 XB02C0390B51 Diff −0.5 3.3 0.5 0.6 XB02C03 90B51 Prob 0.1363 0.656 0.5958 SDVIGOILT PROT G/C Variety1 Variety2 Statistic score ABS pct ABS pct ABScount ABS XB02C03 90B51 Mean1 6 21.1 40.4 15 XB02C03 90B51 Mean2 5.621.2 41.7 15.9 XB02C03 90B51 #Locs 3 6 6 6 XB02C03 90B51 #Reps 9 6 6 6XB02C03 90B51 #Years 2 2 2 2 XB02C03 90B51 Diff 0.4 0 −1.3 −0.9 XB02C0390B51 Prob 0.6667 0.8338 0.0001 0.2993

TABLE 2C VARIETY COMPARISON DATA FOR XB02C03 YIELD bu/a MATABS LDGSEVHGT in Variety1 Variety2 Statistic 60# ABS count ABS score ABS ABSXB02C03 90B73 Mean1 38.1 111.3 7 31 XB02C03 90B73 Mean2 41 117 4.5 35XB02C03 90B73 #Locs 8 5 1 3 XB02C03 90B73 #Reps 16 10 2 6 XB02C03 90B73#Years 1 1 1 1 XB02C03 90B73 Diff −3 −5.7 2.5 3 XB02C03 90B73 Prob0.2854 0.0118 0.2907 FEC BSR PRTLAB EMGSC Variety1 Variety2 Statisticscore ABS score ABS score ABS score ABS XB02C03 90B73 Mean1 6.3 7 6.3 6XB02C03 90B73 Mean2 2.4 2.3 6 7 XB02C03 90B73 #Locs 3 1 1 2 XB02C0390B73 #Reps 8 3 3 6 XB02C03 90B73 #Years 1 1 1 1 XB02C03 90B73 Diff 3.94.7 0.3 −1 XB02C03 90B73 Prob 0.0254 0.3743 SDVIG OILT PROT G/C Variety1Variety2 Statistic score ABS pct ABS pct ABS count ABS XB02C03 90B73Mean1 5.7 20.9 40.8 16 XB02C03 90B73 Mean2 8.2 21.4 41.9 17.3 XB02C0390B73 #Locs 2 3 3 3 XB02C03 90B73 #Reps 6 3 3 3 XB02C03 90B73 #Years 1 11 1 XB02C03 90B73 Diff −2.5 −0.5 −1.1 −1.4 XB02C03 90B73 Prob 0.2780.3119 0.2798 0.2007

TABLE 2D VARIETY COMPARISON DATA FOR XB02C03 YIELD bu/a MATABS LDGSEVHGT in Variety1 Variety2 Statistic 60# ABS count ABS score ABS ABSXB02C03 90B74 Mean1 40.6 116.5 6.7 31 XB02C03 90B74 Mean2 41.3 119.8 7.532 XB02C03 90B74 #Locs 16 11 3 4 XB02C03 90B74 #Reps 32 21 6 8 XB02C0390B74 #Years 2 2 2 2 XB02C03 90B74 Diff −0.6 −3.2 −0.8 1 XB02C03 90B74Prob 0.6621 0.0334 0.1994 0.5436 FEC BSR PRTLAB EMGSC Variety1 Variety2Statistic score ABS score ABS score ABS score ABS XB02C03 90B74 Mean16.5 7 5.7 5.9 XB02C03 90B74 Mean2 6.6 6.7 6.3 6.6 XB02C03 90B74 #Locs 51 2 3 XB02C03 90B74 #Reps 14 3 6 9 XB02C03 90B74 #Years 2 1 2 2 XB02C0390B74 Diff −0.2 0.3 −0.7 −0.7 XB02C03 90B74 Prob 0.4734 0.5 0.0742 SDVIGOILT PROT G/C Variety1 Variety2 Statistic score ABS pct ABS pct ABScount ABS XB02C03 90B74 Mean1 6 21.1 40.4 15 XB02C03 90B74 Mean2 6.821.5 40.5 14.9 XB02C03 90B74 #Locs 3 6 6 6 XB02C03 90B74 #Reps 9 6 6 6XB02C03 90B74 #Years 2 2 2 2 XB02C03 90B74 Diff −0.8 −0.4 −0.1 0.1XB02C03 90B74 Prob 0.3975 0.182 0.6606 0.8553

Genetic Marker Profile Through SSR

The present invention also comprises a soybean plant which may becharacterized by molecular and physiological data obtained from therepresentative sample of said variety deposited with the ATCC. Furtherprovided by the invention is a soybean plant formed by the combinationof the disclosed soybean plant or plant cell with another soybean plantor cell and characterized by being heterozygous for the molecular dataof the variety.

In addition to phenotypic observations, a plant can also be identifiedby its genotype. The genotype of a plant can be characterized through agenetic marker profile which can identify plants of the same variety ora related variety or be used to determine or validate a pedigree.Genetic marker profiles can be obtained by techniques such asRestriction Fragment Length Polymorphisms (RFLPs), Randomly AmplifiedPolymorphic DNAs (RAPDs), Arbitrarily Prirhed Polymerase Chain Reaction(AP-PCR), DNA Amplification Fingerprinting (DAF), Sequence CharacterizedAmplified Regions (SCARs), Amplified Fragment Length Polymorphisms(AFLPs), Simple Sequence Repeats (SSRs) which are also referred to asMicrosatellites, and Single Nucleotide Polymorphisms (SNPs). Forexample, see Cregan et. al, “An Integrated Genetic Linkage Map of theSoybean Genome” Crop Science 39:1464-1490 (1999), which is incorporatedby reference herein in its entirety.

Particular markers used for these purposes are not limited to anyparticular set of markers, but are envisioned to include any type ofmarker and marker profile which provides a means of distinguishingvarieties. One method of comparison is where only the loci for whichXB02C03 is homozygous are used. For example, one set of publiclyavailable markers which could be used to screen and identify varietyXB02C03 is disclosed in Table 3.

TABLE 3 Soybean SSR Marker Set Marker Sctt008 Satt328 Satt495 Satt572Satt372 Satt523 Satt165 Satt582 Satt284 Satt042 Satt389 Satt513 Satt300Satt543 Satt050 Satt186 Satt590 Satt385 Sct137 Satt150 Satt545 Satt567Satt225 Satt213 Satt540 Satt133 Satt384 Satt175 Satt411 Satt551 Satt233Satt598 Satt250 Satt327 Satt204 Satt336 Satt421 Satt602 Satt470 Satt452Satt255 Satt455 Satt234 Satt409 Satt193 Satt257 Satt228 Satt348 Sct188Satt358 Satt426 Satt144 Satt259 Satt509 Sat090 Satt420 Satt251 Satt262Satt197 Satt594 Satt478 Satt303 Satt592 Satt577 Satt517 Satt153 Satt467Sat117 Satt243 Sct034 Sct187 Satt304 Satt601 Satt353 Satt556 Satt568Satt122 Sctt009 Satt534 Satt279 Satt142 Satt565 Sct186 Satt451 Satt227Satt367 Satt432 Satt127 Satt457 Sctt012 Satt557 Satt270 Sct028 Sat104Satt357 Satt440 Satt532 Satt249 Satt221 Sct046 Satt383 Satt596 Satt295Satt380 Satt507 Satt183 Satt147 Satt431 Satt216 Satt102 Satt266 Satt555Satt412 Satt441 Satt546 Satt475 Satt172 Satt196

Primers and PCR protocols for assaying these markers are disclosed atthe world wide web 129.186.26.94/SSR.html. In addition to being used foridentification of soybean variety XB02C03, a soybean plant producedthrough the use of XB02C03, and the identification or verification ofpedigree for progeny plants produced through the use of XB02C03, thegenetic marker profile is also useful in breeding and developingbackcross conversions.

Means of performing genetic marker profiles using SSR polymorphisms arewell known in the art. SSRs are genetic markers based on polymorphismsin repeated nucleotide sequences, such as microsatellites. A markersystem based on SSRs can be highly informative in linkage analysisrelative to other marker systems in that multiple alleles may bepresent. Another advantage of this type of marker is that, through useof flanking primers, detection of SSRs can be achieved, for example, bythe polymerase chain reaction (PCR), thereby eliminating the need forlabor-intensive Southern hybridization. The PCR™ detection is done byuse of two oligonucleotide primers flanking the polymorphic segment ofrepetitive DNA. Repeated cycles of heat denaturation of the DNA followedby annealing of the primers to their complementary sequences at lowtemperatures, and extension of the annealed primers with DNA polymerase,comprise the major part of the methodology.

Following amplification, markers can be scored by gel electrophoresis ofthe amplification products. Scoring of marker genotype is based on thesize of the amplified fragment as measured by molecular weight (MW)rounded to the nearest integer. While variation in the primer used or inlaboratory procedures can affect the reported molecular weight, relativevalues should remain constant regardless of the specific primer orlaboratory used. When comparing varieties it is preferable if all SSRprofiles are performed in the same lab.

Primers used are publicly available and may be found in the Soybasesupra. or Cregan supra. See also, PCT Publication No. WO 99/31964Nucleotide Polymorphisms in Soybean, U.S. Pat. No. 6,162,967 PositionalCloning of Soybean Cyst Nematode Resistance Genes, and U.S. Ser. No.2002/0129402A1 Soybean Sudden Death Syndrome Resistant Soybeans andMethods of Breeding and Identifying Resistant Plants, the disclosure ofwhich are incorporated herein by reference.

The SSR profile of soybean plant XB02C03 can be used to identify plantscomprising XB02C03 as a parent, since such plants will comprise the samealleles as XB02C03. Because the soybean variety is essentiallyhomozygous at all relevant loci, an inbred should, in almost all cases,have only one allele at each locus. In contrast, a genetic markerprofile of an F1 progeny should be the sum of those parents, e.g., ifone parent had the allele 112 (base pairs) at a particular locus, andthe other parent had 198 the F1 progeny is 112.198 (heterozygous) byinference. Subsequent generations of progeny produced by selection andbreeding are expected to be of genotype 112 (homozygous), 198(homozygous), or 112.198 for that locus position. When the F1 plant isselfed or sibbed for successive filial generations, the locus should beeither 112 or 198 for that position.

In addition, plants and plant parts substantially benefiting from theuse of XB02C03 in their development such as XB02C03 comprising abackcross conversion, transgene, or genetic sterility factor, may beidentified by having a molecular marker profile with a high percentidentity to XB02C03. Such a percent identity might be 95%, 96%, 97%,98%, 99%, 99.5% or 99.9% identical to XB02C03.

The SSR profile of XB02C03 also can be used to identify essentiallyderived varieties and other progeny varieties developed from the use ofXB02C03, as well as cells and other plant parts thereof. Progeny plantsand plant parts produced using XB02C03 may be identified by having amolecular marker profile of at least 25%, 30%, 35%, 40%, 45%, 50%, 55%,60%, 65%, 70%, 75%, 79%, 80%, 81%, 82% 83%, 84%, 85%, 86%, 87%, 88%,89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 99.5% geneticcontribution from soybean variety. Such plants may be developed usingthe markers identified in WO 00/31964, U.S. Pat. No. 6,162,967 and U.S.Ser. No. 2002/0129402A1.

Unique SSR Profiles

While determining the SSR genetic marker profile of the plants describedsupra, several unique SSR profiles may be identified which did notappear in either parent of such plant. Such unique SSR profiles mayarise during the breeding process from recombination or mutation. Acombination of several unique alleles provides a means of identifying aplant variety, an F1 progeny produced from such variety, and progenyproduced from such variety. Such progeny may be further characterized asbeing within a pedigree distance of XB02C03, such as within 1,2,3,4 or 5or less cross-pollinations to a soybean plant other than XB02C03 or aplant that has XB02C03 as a progenitor. Unique molecular profiles may beidentified with other molecular tools such as SNPs and RFLPs.

The goal of soybean breeding is to develop new, unique and superiorsoybean varieties. In practical application of a chosen soybean breedingprogram, the breeder initially selects and crosses two or more parentalvarieties, followed by repeated selfing and selection, producing manynew genetic combinations. Once a particular variety is used in a soybeanprogram, each resultant cross thereafter will retain the benefit of theuse of the initial parent. Each and every cross made from a varietyXB02C03 provides benefit to the breeder resulting from the uniquecombination of alleles present in variety XB02C03 that are not presentin any other plant. Soybean variety XB02C03 was selected not only forits own beneficial agronomic traits but also for its favorable breedingcharacteristics. Use of XB02C03 as a source of breeding material confersbenefit far beyond an initial cross and provides a benefit to an entirebreeding program which uses XB02C03 as a source of germplasm. Twobreeders will never develop the same variety, or even very similarvarieties, having the same soybean traits and the use of variety XB02C03in a breeding program provides benefits from the favorable combinationof not just agronomic traits but also traits which confer a breedingadvantage.

Each year, the plant breeder selects the germplasm to advance to thenext generation. This germplasm is grown under unique and differentgeographical, climatic and soil conditions, and further selections arethen made during and at the end of the growing season.

Proper testing should detect major faults and establish the level ofsuperiority or improvement over current varieties. In addition toshowing superior performance, there must be a demand for a new variety.The new variety must be compatible with industry standards, or mustcreate a new market. The introduction of a new variety may incuradditional costs to the seed producer, the grower, processor andconsumer, for special advertising and marketing, altered seed andcommercial production practices, and new product utilization. Thetesting preceding release of a new variety should take intoconsideration research and development costs as well as technicalsuperiority of the final variety. For seed-propagated varieties, it mustbe feasible to produce seed easily and economically. Preferably residualheterozygosity should not exceed 5%.

FURTHER EMBODIMENTS OF THE INVENTION

The seed of the soybean variety of the invention, the plant producedfrom the seed, the F1 progeny soybean plant produced from the crossingof the variety with any other soybean plant, F1 seed, and various partsof the F1 soybean plant are all intended to be within the scope of theinvention. These plants and parts can be utilized for human food,livestock feed, as a raw material in industry, or as breeding materialfor development of other soybean varieties.

Certain changes and modifications such as single gene modifications andmutations, somoclonal variants, the creation of male sterile versions,creation of hybrids, variant individuals selected from large populationsof the plants of the instant variety and the like may be practicedwithin the scope of the invention. These modifications may be created bymethods such as backcrossing, transformation, creations of hybrids andthe like.

Another such embodiment is the method of crossing soybean varietyXB02C03 with another soybean plant, such as a different soybean variety,to form a first generation population of F1 hybrid plants. Thepopulation of first generation F1 hybrid plants produced by this methodis also an embodiment of the invention. This first generation populationof F1 plants will comprise an essentially complete set of the alleles ofsoybean variety XB02C03. One of ordinary skill in the art can utilizeeither breeder books or molecular methods to identify a particular F1hybrid plant produced using soybean variety XB02C03, and any suchindividual plant is also encompassed by this invention. Theseembodiments also cover use of these methods with transgenic or backcrossconversions of soybean variety XB02C03.

Another such embodiment of this invention is a method of using soybeanvariety XB02C03 in breeding that involves the repeated backcrossing tosoybean variety XB02C03 any number of times. Using backcrossing methods,or even the tissue culture and transgenic methods described herein, thebackcross conversion methods described herein, or other breeding methodsknown to one of ordinary skill in the art, one can develop individualplants, plant cells, and populations of plants that retain at least 25%,30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 79%, 80%, 81%, 82%,83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%,97%, 98%, 99% or 99.5% genetic contribution from soybean varietyXB02C03. The percentage of the genetics retained in the progeny may bemeasured by either pedigree analysis or through the use of genetictechniques such as molecular markers or electrophoresis. In usingpedigree analysis one would determine that on average, 50% of thestarting germplasm would be passed to the progeny variety after onecross to another variety, 25% after another cross to a differentvariety, and so on. Molecular markers could also be used to confirmand/or determine the pedigree of the progeny variety.

One method for producing a variety derived from soybean variety XB02C03is as follows. One of ordinary skill in the art would obtain a seed fromthe cross between soybean variety XB02C03 and another variety ofsoybean, such as an elite variety. The F1 seed derived from this crosswould be grown to form a homogeneous population. The F1 seed wouldcontain essentially all of the alleles from variety XB02C03 andessentially all of the alleles from the other soybean variety. The F1nuclear genome would be made-up of 50% variety XB02C03 and 50% of theother elite variety. The F1 seed would be grown and allowed to self,thereby forming F2 seed. On average the F2 seed would have derived 50%of its alleles from variety XB02C03 and 50% from the other soybeanvariety, but many individual plants from the population would have agreater percentage of their alleles derived from XB02C03 (Wang J. and R.Bernardo, 2000, Crop Sci. 40:659-665 and Bernardo, R. and A. L. Kahler,2001, Theor. Appl. Genet 102:986-992). Molecular markers of XB02C03could be used to select and retain those varieties with high similarityto XB02C03. The F2 seed would be grown and selection of plants would bemade based on visual observation, markers and/or measurement of traits.The traits used for selection may be any XB02C03 trait described in thisspecification, including the soybean variety XB02C03 traits ofmulti-race Phytophthora root rot resistance, a substantial degree ofglyphosate resistance, Brown Stem rot resistance, relative maturitygroup 0, sub-group 2, and particularly adapted to Canada and the NorthCentral and Western areas of the United States. The XB02C03 progenyplants that exhibit one or more of the desired XB02C03 traits, such asthose listed above, would be selected and each plant would be harvestedseparately. This F3 seed from each plant would be grown in individualrows and allowed to self. Then selected rows or plants from the rowswould be harvested individually. The selections would again be based onvisual observation, markers and/or measurements for desirable traits ofthe plants, such as one or more of the desirable XB02C03 traits listedabove. The process of growing and selection would be repeated any numberof times until a XB02C03 progeny plant is obtained. The XB02C03 progenyplant would contain desirable traits derived from soybean plant XB02C03,some of which may not have been expressed by the other variety to whichsoybean variety XB02C03 was crossed and some of which may have beenexpressed by both soybean varieties but now would be at a level equal toor greater than the level expressed in soybean variety XB02C03. However,in each case the resulting progeny variety would benefit from theefforts of the inventor(s), and would not have existed but for theinventor(s) work in creating XB02C03. The XB02C03 progeny plants wouldhave, on average, 50% of their genes derived from variety XB02C03, butmany individual plants from the population would have a greaterpercentage of their alleles derived from XB02C03. This breeding cycle,of crossing and selfing, and optional selection, may be repeated toproduce another population of XB02C03 progeny plants with, on average,25% of their genes derived from variety XB02C03, but again, manyindividual plants from the population would have a greater percentage oftheir alleles derived from XB02C03. Another embodiment of the inventionis a XB02C03 progeny plant that has received the desirable XB02C03traits listed above through the use of XB02C03, which traits were notexhibited by other plants used in the breeding process.

The previous example can be modified in numerous ways, for instanceselection may or may not occur at every selfing generation, selectionmay occur before or after the actual self-pollination process occurs, orindividual selections may be made by harvesting individual pods, plants,rows or plots at any point during the breeding process described. Inaddition, double haploid breeding methods may be used at any step in theprocess. The population of plants produced at each and any cycle ofbreeding is also an embodiment of the invention, and on average eachsuch population would predictably consist of plants containingapproximately 50% of its genes from variety XB02C03 in the firstbreeding cycle, 25% of its genes from variety XB02C03 in the secondbreeding cycle, 12.5% of its genes from variety XB02C03 in the thirdbreeding cycle and so on. However, in each case the use of XB02C03provides a substantial benefit when linkage groups of XB02C03 areretained in the progeny varieties. Thus it provides a significantadvantage to use XB02C03 as starting material to produce a variety thatretains desired genetics or traits of XB02C03.

Another embodiment of this invention is the method of obtaining asubstantially homozygous XB02C03 progeny plant by obtaining a seed fromthe cross of XB02C03 and another soybean plant and applying doublehaploid methods to the F1 seed or F1 plant or to any successive filialgeneration. Based on studies in maize and currently being conducted insoybean, such methods would decrease the number of generations requiredto produce a variety with similar genetics or characteristics toXB02C03. See Bemardo, R. and Kahler, A. L., Theor. Appl. Genet,102:986-992 (2001).

A further embodiment of the invention is a backcross conversion ofXB02C03. A backcross conversion occurs when DNA sequences are introducedthrough traditional (non-transformation) breeding techniques, such asbackcrossing (Hallauer et al, 1988). DNA sequences, whether naturallyoccurring or transgenes, may be introduced using these traditionalbreeding techniques. The term backcross conversion is also referred toin the art as a single locus conversion. Reference is made to U.S. Ser.No. 2002/0062506A1 for a detailed discussion of single locus conversionsand traits that may be incorporated into XB02C03 through backcrossconversion. Desired traits transferred through this process include, butare not limited to, nutritional enhancements, industrial enhancements,disease resistance, insect resistance, herbicide resistance and yieldenhancements. The trait of interest is transferred from the donor parentto the recurrent parent, in this case, the soybean plant disclosedherein. Single gene traits may result from either the transfer of adominant allele or a recessive allele. Selection of progeny containingthe trait of interest is accomplished by direct selection for a traitassociated with a dominant allele. Selection of progeny for a trait thatis transferred via a recessive allele, requires growing and selfing thefirst backcross generation to determine which plants carry the recessivealleles. Recessive traits may require additional progeny testing insuccessive backcross generations to determine the presence of the geneof interest. Along with selection for the trait of interest, progeny areselected for the phenotype of the recurrent parent. It should beunderstood that occasionally additional polynucleotide sequences orgenes are transferred along with the backcross conversion trait ofinterest. A progeny comprising at least 95%, 96%, 97%, 98%, 99%, 99.5%and 99.9% of the genes from the recurrent parent, the soybean varietydisclosed herein, plus comprising the backcross conversion trait ortraits of interest, would be considered to be a backcross conversion ofsoybean variety XB02C03. A progeny plant produced by using soybeanvariety XB02C03 at least 2, 3, 4, 5, 6, 7, or 8 times as a recurrentparent is within the scope of this invention.

As used herein, the term plant includes plant protoplasts, plant celltissue cultures from which soybean plants can be regenerated, plantcalli, plant clumps, and plant cells that are intact in plants or partsof plants, such as embryos, pollen, ovules, seed, flowers, pods, leaves,roots, root tips, anthers, and the like.

All plants produced using soybean variety XB02C03 as a parent are withinthe scope of this invention, including those developed from varietiesderived from soybean variety XB02C03. Advantageously, the soybeanvariety could be used in crosses with other, different, soybean plantsto produce first generation (F1) soybean hybrid seeds and plants withsuperior characteristics. The variety of the invention can also be usedfor transformation where exogenous genes are introduced and expressed bythe variety of the invention. Genetic variants created either throughtraditional breeding methods using variety XB02C03 or throughtransformation of XB02C03 by any of a number of protocols known to thoseof skill in the art are intended to be within the scope of thisinvention.

Transformation of Soybean

The advent of new molecular biological techniques have allowed theisolation and characterization of genetic elements with specificfunctions, such as encoding specific protein products. Scientists in thefield of plant biology developed a strong interest in engineering thegenome of plants to contain and express foreign genetic elements, oradditional, or modified versions of native or endogenous geneticelements in order to alter the traits of a plant in a specific manner.Any DNA sequences, whether from a different species or from the samespecies, that are inserted into the genome using transformation arereferred to herein collectively as “transgenes”. Over the last fifteento twenty years several methods for producing transgenic plants havebeen developed, and the present invention, in particular embodiments,also relates to transformed versions of the soybean variety XB02C03.

Numerous methods for plant transformation have been developed, includingbiological and physical, plant transformation protocols. See, forexample, Miki et al., “Procedures for Introducing Foreign DNA intoPlants” in Methods in Plant Molecular Biology and Biotechnology, Glick,B. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993) pages67-88. In addition, expression vectors and in vitro culture methods forplant cell or tissue transformation and regeneration of plants areavailable. See, for example, Gruber et al., “Vectors for PlantTransformation” in Methods in Plant Molecular Biology and Biotechnology,Glick, B. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton,1993) pages 89-119.

The most prevalent types of plant transformation involve theconstruction of an expression vector. Such a vector comprises a DNAsequence that contains a gene under the control of or operatively linkedto a regulatory element, for example a promoter. The vector may containone or more genes and one or more regulatory elements.

Various genetic elements can be introduced into the plant genome usingtransformation. These elements include but are not limited to genes;coding sequences; inducible, constitutive, and tissue specificpromoters; enhancing sequences; and signal and targeting sequences. SeeU.S. Pat. No. 6,162,968, which is herein incorporated by reference.

A genetic trait which has been engineered into a particular soybeanplant using transformation techniques, could be moved into anothervariety using traditional breeding techniques that are well known in theplant breeding arts. For example, a backcrossing approach could be usedto move a transgene from a transformed soybean plant to an elite soybeanvariety and the resulting progeny would comprise a transgene. As usedherein, “crossing” can refer to a simple X by Y cross, or the process ofbackcrossing, depending on the context. The term “cross” excludes theprocesses of selfing or sibbing.

With transgenic plants according to the present invention, a foreignprotein can be produced in commercial quantities. Thus, techniques forthe selection and propagation of transformed plants, which are wellunderstood in the art, yield a plurality of transgenic plants which areharvested in a conventional manner, and a foreign protein then can beextracted from a tissue of interest or from total biomass. Proteinextraction from plant biomass can be accomplished by known methods whichare discussed, for example, by Heney and Orr, Anal. Biochem. 114: 92-6(1981). In one embodiment, the biomass of interest is seed.

A genetic map can be generated, primarily via conventional RFLP, PCR,and SSR analysis, which identifies the approximate chromosomal locationof the integrated DNA molecule. For exemplary methodologies in thisregard, see Glick and Thompson, METHODS IN PLANT MOLECULAR BIOLOGY ANDBIOTECHNOLOGY 269-284 (CRC Press, Boca Raton, 1993). Map informationconcerning chromosomal location is useful for proprietary protection ofa subject transgenic plant. If unauthorized propagation is undertakenand crosses made with other germplasm, the map of the integration regioncan be compared to similar maps for suspect plants, to determine if thelatter have a common parentage with the subject plant. Map comparisonswould involve hybridizations, RFLP, PCR, SSR and sequencing, all ofwhich are conventional techniques.

Likewise, by means of the present invention, agronomic genes can beexpressed in transformed plants. More particularly, plants can begenetically engineered to express various phenotypes of agronomicinterest. Through the transformation of soybean the expression of genescan be modulated to enhance disease resistance, insect resistance,herbicide resistance, agronomic traits as well as grain quality traits.Transformation can also be used to insert DNA sequences which control orhelp control male-sterility. DNA sequences native to soybean as well asnon-native DNA sequences can be transformed into soybean and used tomodulate levels of native or non-native proteins. Anti-sense technology,various promoters, targeting sequences, enhancing sequences, and otherDNA sequences can be inserted into the soybean genome for the purpose ofmodulating the expression of proteins. Exemplary genes implicated inthis regard include, but are not limited to, those categorized below.

1. Genes that Confer Resistance to Pests or Disease and that Encode:

(A) Plant disease resistance genes. Plant defenses are often activatedby specific interaction between the product of a disease resistance gene(R) in the plant and the product of a corresponding avirulence (Avr)gene in the pathogen. A plant variety can be transformed with a clonedresistance gene to engineer plants that are resistant to specificpathogen strains. See, for example Jones et al., Science 266: 789 (1994)(cloning of the tomato Cf-9 gene for resistance to Cladosporium fulvum);Martin et al., Science 262: 1432 (1993) (tomato Pto gene for resistanceto Pseudomonas syringae pv. tomato encodes a protein kinase); Mindrinoset al., Cell 78: 1089 (1994) (Arabidopsis RSP2 gene for resistance toPseudomonas syringae).

(B) A gene conferring resistance to a pest, such as soybean cystnematode. See e.g. PCT Application WO96/30517; PCT ApplicationWO93/19181.

(C) A Bacillus thuringiensis protein, a derivative thereof or asynthetic polypeptide modeled thereon. See, for example, Geiser et al.,Gene 48: 109 (1986), who disclose the cloning and nucleotide sequence ofa Bt delta-endotoxin gene. Moreover, DNA molecules encodingdelta-endotoxin genes can be purchased from American Type CultureCollection (Manassas, Va.), for example, under ATCC Accession Nos.40098, 67136, 31995 and 31998. Other examples of Bacillus thuringiensistransgenes being genetically engineered are given in the followingpatents and hereby are incorporated by reference: U.S. Pat. Nos.5,188,960; 5,689,052; 5,880,275; and WO 97/40162.

(D) A lectin. See, for example, the disclosure by Van Damme et al.,Plant Molec. Biol. 24: 25 (1994), who disclose the nucleotide sequencesof several Clivia miniata mannose-binding lectin genes.

(E) A vitamin-binding protein such as avidin. See PCT application U.S.Ser. No. 93/06487, the contents of which are hereby incorporated byreference. The application teaches the use of avidin and avidinhomologues as larvicides against insect pests.

(F) An enzyme inhibitor, for example, a protease or proteinase inhibitoror an amylase inhibitor. See, for example, Abe et al., J. Biol. Chem.262: 16793 (1987) (nucleotide sequence of rice cysteine proteinaseinhibitor), Huub et al., Plant Molec. Biol. 21: 985 (1993) (nucleotidesequence of cDNA encoding tobacco proteinase inhibitor I), Sumitani etal., Biosci. Biotech. Biochem. 57: 1243 (1993) (nucleotide sequence ofStreptomyces nitrosporeus alpha-amylase inhibitor) and U.S. Pat. No.5,494,813 (Hepher and Atkinson, issued Feb. 27, 1996).

(G) An insect-specific hormone or pheromone such as an ecdysteroid andjuvenile hormone, a variant thereof, a mimetic based thereon, or anantagonist or agonist thereof. See, for example, the disclosure byHammock et al., Nature 344: 458 (1990), of baculovirus expression ofcloned juvenile hormone esterase, an inactivator of juvenile hormone.

(H) An insect-specific peptide or neuropeptide which, upon expression,disrupts the physiology of the affected pest. For example, see thedisclosures of Regan, J. Biol. Chem. 269: 9 (1994) (expression cloningyields DNA coding for insect diuretic hormone receptor), and Pratt etal., Biochem. Biophys. Res. Comm. 163: 1243 (1989) (an allostatin isidentified in Diploptera puntata). See also U.S. Pat. No. 5,266,317 toTomalski et al., who disclose genes encoding insect-specific, paralyticneurotoxins.

(I) An insect-specific venom produced in nature by a snake, a wasp, etc.For example, see Pang et al., Gene 116: 165 (1992), for disclosure ofheterologous expression in plants of a gene coding for a scorpioninsectotoxic peptide.

(J) An enzyme responsible for an hyperaccumulation of a monoterpene, asesquiterpene, a steroid, hydroxamic acid, a phenylpropanoid derivativeor another non-protein molecule with insecticidal activity.

(K) An enzyme involved in the modification, including thepost-translational modification, of a biologically active molecule; forexample, a glycolytic enzyme, a proteolytic enzyme, a lipolytic enzyme,a nuclease, a cyclase, a transaminase, an esterase, a hydrolase, aphosphatase, a kinase, a phosphorylase, a polymerase, an elastase, achitinase and a glucanase, whether natural or synthetic. See PCTapplication WO 93/02197 in the name of Scott et al., which discloses thenucleotide sequence of a callase gene. DNA molecules which containchitinase-encoding sequences can be obtained, for example, from the ATCCunder Accession Nos. 39637 and 67152. See also Kramer et al., InsectBiochem. Molec. Biol. 23: 691 (1993), who teach the nucleotide sequenceof a cDNA encoding tobacco hookworm chitinase, and Kawalleck et al.,Plant Molec. Biol. 21: 673 (1993), who provide the nucleotide sequenceof the parsley ubi4-2 polyubiquitin gene.

(L) A molecule that stimulates signal transduction. For example, see thedisclosure by Botella et al., Plant Molec. Biol. 24: 757 (1994), ofnucleotide sequences for mung bean calmodulin cDNA clones, and Griess etal., Plant Physiol. 104: 1467 (1994), who provide the nucleotidesequence of a maize calmodulin cDNA clone.

(M) A hydrophobic moment peptide. See PCT application WO95/16776(disclosure of peptide derivatives of Tachyplesin which inhibit fungalplant pathogens) and PCT application WO95/18855 (teaches syntheticantimicrobial peptides that confer disease resistance), the respectivecontents of which are hereby incorporated by reference.

(N) A membrane permease, a channel former or a channel blocker. Forexample, see the disclosure by Jaynes et al., Plant Sci. 89: 43 (1993),of heterologous expression of a cecropin-beta lytic peptide analog torender transgenic tobacco plants resistant to Pseudomonas solanacearum.

(O) A viral-invasive protein or a complex toxin derived therefrom. Forexample, the accumulation of viral coat proteins in transformed plantcells imparts resistance to viral infection and/or disease developmenteffected by the virus from which the coat protein gene is derived, aswell as by related viruses. See Beachy et al., Ann. Rev. Phytopathol.28: 451 (1990). Coat protein-mediated resistance has been conferred upontransformed plants against alfalfa mosaic virus, cucumber mosaic virus,tobacco streak virus, potato virus X, potato virus Y, tobacco etchvirus, tobacco rattle virus and tobacco mosaic virus. Id. See also, Wanget al, Molecular Breeding 8: 119-127 (2001), Pathogen-Derived Resistanceto Soybean Mosaic Virus in Soybean.

(P) An insect-specific antibody or an immunotoxin derived therefrom.Thus, an antibody targeted to a critical metabolic function in theinsect gut would inactivate an affected enzyme, killing the insect. Cf.Taylor et al., Abstract #497, SEVENTH INT'L SYMPOSIUM ON MOLECULARPLANT-MICROBE INTERACTIONS (Edinburgh, Scotland, 1994) (enzymaticinactivation in transgenic tobacco via production of single-chainantibody fragments).

(Q) A virus-specific antibody. See, for example, Tavladoraki et al.,Nature 366: 469 (1993), who show that transgenic plants expressingrecombinant antibody genes are protected from virus attack.

(R) A developmental-arrestive protein produced in nature by a pathogenor a parasite. Thus, fungal endo alpha-1,4-D-polygalacturonasesfacilitate fungal colonization and plant nutrient release bysolubilizing plant cell wall homo-alpha-1,4-D-galacturonase. See Lamb etal., Bio/Technology 10: 1436 (1992). The cloning and characterization ofa gene which encodes a bean endopolygalacturonase-inhibiting protein isdescribed by Toubart et al., Plant J. 2: 367 (1992).

(S) A developmental-arrestive protein produced in nature by a plant. Forexample, Logemann et al., Bio/Technology 10: 305 (1992), have shown thattransgenic plants expressing the barley ribosome-inactivating gene havean increased resistance to fungal disease.

(T) Genes involved in the Systemic Acquired Resistance (SAR) Responseand/or the pathogenesis related genes. Briggs, S., Current Biology, 5(2)(1995).

(U) Antifungal genes (Cornelissen and Melchers, PI. Physiol.101:709-712, (1993) and Parijs et al., Planta 183:258-264, (1991) andBushnell et al., Can. J. of Plant Path. 20(2):137-149 (1998).

(V) Genes that confer resistance to Phytophthora Root Rot, such as theRps 1, Rps 1-a, Rps 1-b, Rps 1-c, Rps 1-d, Rps 1-e, Rps 1-k, Rps 2, Rps3-a, Rps 3-b, Rps 3-c, Rps 4, Rps 5, Rps 6, Rps 7 and other Rps genes.See, for example, Shoemaker et al, Phytophthora Root Rot Resistance GeneMapping in Soybean, Plant Genome IV Conference, San Diego, Calif.(1995).

(W) Genes that confer resistance to Brown Stem Rot, such as described inU.S. Pat. No. 5,689, 035 and incorporated by reference for this purpose.

2. Genes that Confer Resistance to a Herbicide, for Example:

(A) A herbicide that inhibits the growing point or meristem, such as animidazolinone or a sulfonylurea. Exemplary genes in this category codefor mutant ALS and AHAS enzyme as described, for example, by Lee et al.,EMBO J. 7: 1241 (1988), and Miki et al., Theor. Appl. Genet. 80: 449(1990), respectively. See also, U.S. Pat. Nos. 5,605,011; 5,013,659;5,141,870; 5,767,361: 5,731,180; 5,304,732; 4,761,373; 5,331,107;5,928,937; and 5,378,824; and international publication WO 96/33270,which are incorporated herein by reference in their entireties for allpurposes.

(B) Glyphosate (resistance imparted by mutant5-enolpyruvl-3-phosphikimate synthase (EPSP) and aroA genes,respectively) and other phosphono compounds such as glufosinate(phosphinothricin acetyl transferase, PAT) and Streptomyceshygroscopicus phosphinothricin-acetyl transferase, bar, genes), andpyridinoxy or phenoxy propionic acids and cycloshexones (ACCaseinhibitor-encoding genes). See, for example, U.S. Pat. No. 4,940,835 toShah et al., which discloses the nucleotide sequence of a form of EPSPSwhich can confer glyphosate resistance. U.S. Pat. No. 5,627,061 to Barryet al. describes genes encoding EPSPS enzymes. See also U.S. Pat. Nos.6,248,876 B1; 6,040,497; 5,804,425; 5,633,435; 5,145,783; 4,971,908;5,312,910; 5,188,642; 4,940,835; 5,866,775; 6,225,114 B1; 6,130,366;5,310,667; 4,535,060; 4,769,061; 5,633,448; 5,510,471; Re. 36,449; RE37,287 E; and 5,491,288; and international publications WO 97/04103;WO97104114; WO 00/66746; WO 01/66704; WO 00/66748 and WO 00/66747, whichare incorporated herein by reference in their entireties for allpurposes. Glyphosate resistance is also imparted to plants that expressa gene that encodes a glyphosate oxido-reductase enzyme as describedmore fully in U.S. Pat. Nos. 5,776,760 and 5,463,175, which areincorporated herein by reference in their entireties for all purposes.In addition glyphosate resistance can be imparted to plants by the overexpression of genes encoding glyphosate N-acetyltransferase. See, forexample, U.S. application Ser. Nos. 60/244,385; 60/377,175 and60/377,719.

A DNA molecule encoding a mutant aroA gene can be obtained under ATCC isAccession No. 39256, and the nucleotide sequence of the mutant gene isdisclosed in U.S. Pat. No. 4,769,061 to Comai. European patentapplication No. 0 333 033 to Kumada et al. and U.S. Pat. No. 4,975,374to Goodman et al. disclose nucleotide sequences of glutamine synthetasegenes which confer resistance to herbicides such as L-phosphinothricin.The nucleotide sequence of a phosphinothricin-acetyl-transferase gene isprovided in European application No. 0 242 246 to Leemans et al. DeGreef et al., Bio/Technology 7: 61 (1989), describe the production oftransgenic plants that express chimeric bar genes coding forphosphinothricin acetyl transferase activity. See also, U.S. Pat. Nos.5,969,213; 5,489,520; 5,550,318; 5,874,265; 5,919,675; 5,561,236;5,648,477; 5,646,024; 6,177,616 B1; and 5,879,903, which areincorporated herein by reference in their entireties for all purposes.Exemplary of genes conferring resistance to phenoxy propionic acids andcycloshexones, such as sethoxydim and haloxyfop, are the Acc1-S1,Acc1-S2 and Acc1-S3 genes described by Marshall et al., Theor. Appl.Genet. 83: 435 (1992).

(C) A herbicide that inhibits photosynthesis, such as a triazine (psbAand gs+genes) and a benzonitrile (nitrilase gene). Przibilla et al.,Plant Cell 3: 169 (1991), describe the transformation of Chlamydomonaswith plasmids encoding mutant psbA genes. Nucleotide sequences fornitrilase genes are disclosed in U.S. Pat. No. 4,810,648 to Stalker, andDNA molecules containing these genes are available under ATCC AccessionNos. 53435, 67441 and 67442. Cloning and expression of DNA coding for aglutathione S-transferase is described by Hayes et al., Biochem. J.285:173 (1992).

(D) Acetohydroxy acid synthase, which has been found to make plants thatexpress this enzyme resistant to multiple types of herbicides, has beenintroduced into a variety of plants (see, e.g., Hattori et al. (1995)Mol Gen Genet 246:419). Other genes that confer tolerance to herbicidesinclude: a gene encoding a chimeric protein of rat cytochrome P4507A1and yeast NADPH-cytochrome P450 oxidoreductase (Shiota et al. (1994)Plant PhysiolPlant Physiol 106:17), genes for glutathione reductase andsuperoxide dismutase (Aono et al. (1995) Plant Cell Physiol 36:1687, andgenes for various phosphotransferases (Datta et al. (1992) Plant MolBiol 20:619).

(E) Protoporphyrinogen oxidase (protox) is necessary for the productionof chlorophyll, which is necessary for all plant survival. The protoxenzyme serves as the target for a variety of herbicidal compounds. Theseherbicides also inhibit growth of all the different species of plantspresent, causing their total destruction. The development of plantscontaining altered protox activity which are resistant to theseherbicides are described in U.S. Pat. Nos. 6,288,306 B1; 6,282,837 B1;and 5,767,373; and international publication WO 01/12825, which areincorporated herein by reference in their entireties for all purposes.

3. Genes that Confer or Contribute to a Grain Trait, Such as:

(A) Modified fatty acid metabolism, for example, by transforming a plantwith an antisense gene of stearoyl-ACP desaturase to increase stearicacid content of the plant. See Knultzon et al., Proc. Nat'l. Acad. Sci.USA 89: 2624 (1992).

(B) Decreased phytate content

(1) Introduction of a phytase-encoding gene would enhance breakdown ofphytate, adding more free phosphate to the transformed plant. Forexample, see Van Hartingsveldt et al., Gene 127: 87 (1993), for adisclosure of the nucleotide sequence of an Aspergillus niger phytasegene.

(2) A gene could be introduced that reduces phytate content. In maize,this, for example, could be accomplished, by cloning and thenreintroducing DNA associated with the single allele which is responsiblefor maize mutants characterized by low levels of phytic acid. See Raboyet al., Maydica 35: 383 (1990).

(C) Modified carbohydrate composition effected, for example, bytransforming plants with a gene coding for an enzyme that alters thebranching pattern of starch. See Shiroza et al., J. Bacteriol. 170: 810(1988) (nucleotide sequence of Streptococcus mutans fructosyltransferasegene), Steinmetz et al., Mol. Gen. Genet. 200: 220 (1985) (nucleotidesequence of Bacillus subtilis levansucrase gene), Pen et al.,Bio/Technology 10: 292 (1992) (production of transgenic plants thatexpress Bacillus licheniformis alpha-amylase), Elliot et al., PlantMolec. Biol. 21: 515 (1993) (nucleotide sequences of tomato invertasegenes), SØgaard et al., J. Biol. Chem. 268: 22480 (1993) (site-directedmutagenesis of barley alpha-amylase gene), and Fisher et al., PlantPhysiol. 102: 1045 (1993) (maize endosperm starch branching enzyme II).Also, genes that encode for galactinol synthase, such as in U.S. Pat.No. 5,648,210 and U.S. Pat. No. 5,773,699, or genes that encode forraffinose synthetic enzymes, such as U.S. Pat. 6,166,292, EP0994186 andWO0177306.

(D) Elevated oleic acid via FAD-2 gene modification and/or decreasedlinolenic acid via FAD-3 gene modification (see U.S. Pat. Nos.6,063,947; 6,323,392; and WO 93/11245).

4. Genes that Control Male-sterility

(A) Introduction of a deacetylase gene under the control of atapetum-specific promoter and with the application of the chemicalN-Ac-PPT (WO 01/29237).

(B) Introduction of various stamen-specific promoters (WO 92/13956, WO92/13957).

(C) Introduction of the barnase and the barstar gene (Paul et al. PlantMol. Biol. 19:611-622, 1992).

Numerous methods for plant transformation have been developed, includingbiological and physical, plant transformation protocols. See, forexample, Miki et al., “Procedures for Introducing Foreign DNA intoPlants” in Methods in Plant Molecular Biology and Biotechnology, Glick,B. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993) pages67-88. In addition, expression vectors and in vitro culture methods forplant cell or tissue transformation and regeneration of plants areavailable. See, for example, Gruber et al., “Vectors for PlantTransforrnation” in Methods in Plant Molecular Biology andBiotechnology, Glick, B. R. and Thompson, J. E. Eds. (CRC Press, Inc.,Boca Raton, 1993) pages 89-119. See also, U.S. Pat. No. 5,563,055,(Townsend and Thomas), issued Oct. 8, 1996; U.S. Pat. No. 5,015,580(Christou, et al), issued May 14,1991; U.S. Pat. No. 5,322,783 (Tomes,et al.), issued Jun. 21, 1994. Two methods that can be utilized areAgromediated transformation and direct gene transfer. See U.S. Pat. No.6,162,968, which is herein incorporated by reference.

This invention also is directed to methods for producing a soybean plantby crossing a first parent soybean plant with a second parent soybeanplant wherein the first or second parent soybean plant is a soybeanplant of the variety XB02C03. Further, both first and second parentsoybean plants can come from the soybean variety XB02C03. Still further,this invention also is directed to methods for producing XB02C03-derivedsoybean plant by crossing soybean variety XB02C03 with a soybean plantand growing the progeny seed, and repeating the crossing and growingsteps with the XB02C03-derived soybean plant from 1 to 2 times, 1 to 3times, 1 to 4 times, or 1 to 5 times. Thus, any such methods usingsoybean variety XB02C03 are part of this invention: selfing,backcrosses, hybrid production, crosses to populations, and the like.All plants produced using soybean variety XB02C03 as a parent are withinthe scope of this invention, including plants derived from soybeanvariety XB02C03. This includes varieties essentially derived fromvariety XB02C03 with the term “essentially derived variety” having themeaning ascribed to such term in 7 U.S.C. § 2104(a)(3) of the PlantVariety Protection Act, which definition is hereby incorporated byreference. The invention also includes progeny plants and parts thereofwith at least one ancestor that is XB02C03, and more specifically, wherethe pedigree of the progeny includes 1, 2, 3, 4, and/or 5 or lesscross-pollinations to a soybean plant other than XB02C03 or a plant thathas XB02C03 as a progenitor. All breeders of ordinary skill in the artmaintain pedigree records of their breeding programs. These pedigreerecords contain a detailed description of the breeding process, indudinga listing of all parental varieties used in the breeding process andinformation on how such variety was used. Thus, a breeder would know ifXB02C03 were used in the development of a progeny variety, and wouldalso know how many crosses to a plant or variety other than XB02C03 or aplant or variety with XB02C03 as a progenitor were made in thedevelopment of any progeny variety. The soybean variety may also be usedin crosses with other, different soybean plant to produce firstgeneration (F1) soybean seeds and plants with superior characteristics.Specific methods and products produced using soybean variety XB02C03 inplant breeding are encompassed within the scope of the invention listedabove.

The following describes breeding methods that may be used with varietyXB02C03 in the development of further soybean plants. One suchembodiment is a method for developing a XB02C03 progeny soybean plant ina soybean plant breeding program comprising: obtaining the soybeanplant, or its parts, or variety XB02C03 utilizing said plant or plantparts as a source of breeding material; and selecting a XB02C03 progenyplant with molecular markers in common with XB02C03 and/or withmorphological and/or physiological characteristics selected from thecharacteristics listed in Tables 1 or 2. Breeding steps that may be usedin the soybean plant breeding program include pedigree breeding,backcrossing, mutation breeding, and recurrent selection. In conjunctionwith these steps, techniques such as restriction fragment polymorphismenhanced selection, genetic marker enhanced selection (for example SSRmarkers), and the making of double haploids may be utilized.

Another method involves producing a population of variety XB02C03progeny soybean plants, comprising crossing variety XB02C03 with anothersoybean plant, thereby producing a population of soybean plants, which,on average, derive 50% of their alleles from variety XB02C03. A plant ofthis population may be selected and repeatedly selfed or sibbed, with asoybean variety resulting from these successive filial generations. Oneembodiment of this invention is the soybean variety produced by thismethod and that has obtained at least 50% of its alleles from varietyXB02C03.

Field crops are bred through techniques that take advantage of theplant's method of pollination. According to the invention, soybeanvariety XB02C03 may be crossed with self pollinated, sib-pollinated, orcross pollinated to create a pedigree soybean plant. A plant isself-pollinated if pollen from one flower is transferred to the same oranother flower of the same plant. A plant is sib-pollinated whenindividuals within the same family or variety are used for pollination.A plant is cross-pollinated if the pollen comes from a flower on adifferent plant from a different family or variety. The terms“cross-pollination” and “out-cross” as used herein do not includeself-pollination or sib-pollination. Soybean plants (Glycine max), arerecognized to be naturally self-pollinated plants which, while capableof undergoing cross-pollination, rarely do so in nature. Insects arereported by some researchers to carry pollen from one soybean plant toanother and it generally is estimated that less than one percent ofsoybean seed formed in an open planting can be traced tocross-pollination, i.e. less than one percent of soybean seed formed inan open planting is capable of producing F1 hybrid soybean plants, SeeJaycox, “Ecological Relationships between Honey Bees and Soybeans,”appearing in the American Bee Journal Vol. 110(8):

306-307 (August 1970). Thus intervention for control of pollination iscritical to establishment of superior varieties.

A cross between two different homozygous varieties produces a uniformpopulation of hybrid plants that may be heterozygous for many gene loci.A cross of two plants that differ at a number of gene loci will producea population of hybrid plants that differ genetically and will not beuniform. Regardless of parentage, plants that have been self-pollinatedand selected for type for many generations become homozygous at almostall gene loci and produce a uniform population of true breeding progeny.

Soybean variety XB02C03 can be bred by both self-pollination andcross-pollination techniques. Soybean plant breeding programs combinethe genetic backgrounds from two or more lines, varieties or variousother germplasm sources into breeding populations from which new linesor varieties are developed by selfing and selection of desiredphenotypes. Plant breeding and variety, line or hybrid development, aspracticed in a soybean plant breeding program developing significantgenetic advancement, are expensive and time consuming processes

Choice of breeding or selection method used with soybean variety XB02C03depends on the mode of plant reproduction, the heritability of thetrait(s) being improved, and the type of variety used commercially(e.g., F1 hybrid variety, pureline variety, etc.). For highly heritabletraits, a choice of superior individual plants evaluated at a singlelocation will be effective, whereas for traits with low heritability,selection should be based on mean values obtained from replicatedevaluations of families of related plants. Popular selection methodscommonly include pedigree selection, modified pedigree selection, massselection, and recurrent selection.The complexity of inheritanceinfluences choice of the breeding method. In general breeding with thesoybean variety of the invention starts with the crossing of twogenotypes, each of which may have one or more desirable characteristicsthat is lacking in the other or which complements the other. If the twooriginal parentsdo not provide all the desired characteristics, othersources can be included by making more.crosses. In each successivefilial generation, superior plants are selected and self-pollinatedwhich increases the homozygosity of the varieties. Typically in abreeding program five or more successive filial generations of selectionand selfing are practiced: F1→F2; F2→F3; F3→F4; F4→F5, etc. After asufficient amount of inbreeding, successive filial generation will serveto increase seed of the developed variety. Preferably, a developedvariety comprises homozygous allele at about 95% or more of its loci.

Pedigree breeding may be used for the development of XB02C03 soybeanprogeny plants. Two parents that possess favorable, complementary traitsare crossed to produce an F1. An F2 population is produced by selfingone or several F1's or by intercrossing two F1's (sib mating). Selectionof the best individuals may begin in the F2 population; then, beginningin the F3, the best individuals in the successive filial generations areselected. Replicated testing of families can begin in the F4 generationto improve the effectiveness of selection for traits with lowheritability. At an advanced stage of inbreeding (i.e., F6 and F7), thebest varieties or mixtures of phenotypically similar varieties aretested for potential release as new varieties.

Backcross breeding has been used to transfer genes for qualitativetraits, which are highly heritable traits, from a donor parent into adesirable homozygous variety that is utilized as the recurrent parent.For purposes of the invention, soybean variety XB02C03 may be used aseither the donor or recurrent parent for backcross breeding. The sourceof the traits to be transferred is called the donor parent. After theinitial cross, individuals possessing the desired trait or traits of thedonor parent are selected and then repeatedly crossed (backcrossed) withthe recurrent parent. The resulting backcross conversion plant hasessentially the same traits as the recurrent parent (e.g., variety)other than the desirable trait or traits transferred from the donorparent. This approach has been used extensively for breeding diseaseresistant varieties.

Each soybean breeding program should include a periodic, objectiveevaluation of the efficiency of the breeding procedure. Evaluationcriteria vary depending on the goal and objectives, but should includegain from selection per year based on comparisons to an appropriatestandard, overall value of the advanced breeding varieties, and numberof successful varieties produced per unit of input (e.g., per year, perdollar expended, etc.).

Various recurrent selection techniques may be used to improvequantitatively inherited traits controlled by numerous genes. The use ofrecurrent selection in self-pollinating crops depends on the ease ofpollination and the number of hybrid offspring from each successfulcross.

Mass selection and recurrent selection may be used to improvepopulations of either self- or cross-pollinated crops. A geneticallyvariable population of heterozygous individuals is either identified orcreated by intercrossing several different parents. The best plants areselected based on individual superiority, outstanding progeny, orexcellent combining ability. The selected plants are intercrossed toproduce a new population in which further cycles of selection arecontinued.

The single-seed descent procedure in the strict sense refers to plantinga segregating population, harvesting a sample of one seed per plant, andusing the one-seed sample to plant the next generation. When thepopulation has been advanced from the F2 to the desired level ofinbreeding, the plants from which varieties are derived will each traceto different F2 individuals. The number of plants in a populationdeclines each generation due to failure of some seeds to germinate orsome plants to produce at least one seed. As a result, not all of the F2plants originally sampled in the population will be represented by aprogeny when generation advance is completed.

In a multiple-seed procedure, soybean breeders commonly harvest one ormore pods from each plant in a population and thresh them together toform a bulk. Part of the bulk is used to plant the next generation andpart is put in reserve. The procedure has been referred to as modifiedsingle-seed descent or the pod-bulk technique.

The multiple-seed procedure has been used to save labor at harvest. Itis considerably faster to thresh pods with a machine than to remove oneseed from each by hand for the single-seed procedure. The multiple-seedprocedure also makes it possible to plant the same number of seeds of apopulation each generation of inbreeding. Enough seeds are harvested tomake up for those plants that did not germinate or produce seed.

Molecular markers which includes markers identified through the use oftechniques such as such Isozyme Electrophoresis, Restriction FragmentLength Polymorphisms (RFLPs), Randomly Amplified Polymorphic DNAs(RAPDs), Arbitrarily Primed Polymerase Chain Reaction (AP-PCR), DNAAmplification Fingerprinting (DAF), Sequence Characterized AmplifiedRegions (SCARs), Amplified Fragment Length Polymorphisms (AFLPs), SimpleSequence Repeats (SSRs), and Single Nucleotide Polymorphisms (SNPs) maybe used in plant breeding methods. One use of molecular markers isQuantitative Trait Loci (QTL) mapping. QTL mapping is the use ofmarkers, which are known to be closely linked to alleles that havemeasurable effects on a quantitative trait. Selection in the breedingprocess is based upon the accumulation of markers linked to the positiveeffecting alleles and/or the elimination of the markers linked to thenegative effecting alleles from the plant's genome.

Molecular markers can also be used during the breeding process for theselection of qualitative traits. For example, markers closely linked toalleles or markers containing sequences within the actual alleles ofinterest can be used to select plants that contain the alleles ofinterest during a backcrossing breeding program. For example, molecularmarkers are often used in soybean breeding for selection of the trait ofresistance to soybean cyst nematode, See, U.S. Pat. No. 6,162,967. Themarkers can also be used to select for the genome of the recurrentparent and against the markers of the donor parent. Using this procedurecan minimize the amount of genome from the donor parent that remains inthe selected plants. It can also be used to reduce the number of crossesback to the recurrent parent needed in a backcrossing program. The useof molecular markers in the selection process is often called GeneticMarker Enhanced Selection. Molecular markers may also be used toidentify and exclude certain sources of germplasm as parental varietiesor ancestors of a plant by providing a means of tracking geneticprofiles through crosses as discussed more fully hereinafter.

Descriptions of other breeding methods that are commonly used fordifferent traits and crops can be found in one of several referencebooks (e.g., Allard, Principles of Plant Breeding, 1960; Simmonds,Principles of Crop Improvement, 1979; Sneep et al., 1979; Fehr,“Breeding Methods for Cultivar Development”, Chapter 7, SoybeanImprovement, Production and Uses, 2^(nd) ed., Wilcox editor, 1987).

Promising advanced breeding varieties are thoroughly tested and comparedto appropriate standards in environments representative of thecommercial target area(s). The best varieties are candidates for newcommercial varieties; those still deficient in a few traits may be usedas parents to produce new populations for further selection.

A most difficult task is the identification of individuals that aregenetically superior, because for most traits the true genotypic valueis masked by other confounding plant traits or environmental factors.One method of identifying a superior plant is to observe its performancerelative to other experimental plants and to a widely grown standardvariety. Generally a single observation is inconclusive, so replicatedobservations are required to provide a better estimate of its geneticworth.

Thus, even if the entire genotypes of the parents of the breeding crosswere characterized and a desired genotype known, only a few if anyindividuals having the desired genotype may be found in a largesegregating F2 population. It would be very unlikely that a breeder ofordinary skill in the art would be able to recreate the same varietytwice from the very same original parents as the breeder is unable todirect how the genomes combine or how they will interact with theenvironmental conditions. This unpredictability results in theexpenditure of large amounts of research resources in the development ofa superior new soybean variety. Breeders use various methods to helpdetermine which plants should be selected from the segregatingpopulations and ultimately which varieties will be used forcommercialization. In addition to the knowledge of the germplasm andother skills the breeder uses, a part of the selection process isdependent on experimental design coupled with the use of statisticalanalysis. Experimental design and statistical analysis are used to helpdetermine which plants, which family of plants, and finally whichvarieties are significantly better or different for one or more traitsof interest. Experimental design methods are used to assess error sothat differences between two varieties can be more accuratelydetermined. Statistical analysis includes the calculation of meanvalues, determination of the statistical significance of the sources ofvariation, and the calculation of the appropriate variance components.Either a five or a one percent significance levels is customarily usedto determine whether a difference that occurs for a given trait is realor due to the environment or experimental error.

One of ordinary skill in the art of plant breeding would know how toevaluate the traits of two plant varieties to determine if there is nosignificant difference between the two traits expressed by thosevarieties. For example, see Fehr, Walt, Principles of CultivarDevelopment, p. 261-286 (1987) which is incorporated herein byreference. Thus the invention includes soybean variety XB02C03 progenysoybean plants comprising a combination of at least two XB02C03 traitsselected from the group consisting of those listed in Tables 1 and 2 orthe XB02C03 combination of traits listed in the Summary of theInvention, so that said progeny soybean plant is not significantlydifferent for said traits than soybean variety XB02C03 when grown in thesame environment. Using techniques described herein, molecular markersmay be used to identify said progeny plant as an XB02C03 progeny plant.Mean trait values may be used to determine whether trait differences aresignificant, and preferably the traits are measured on plants grownunder the same environmental conditions. Once such a variety isdeveloped its value is substantial since it is important to advance thegermplasm base as a whole in order to maintain or improve traits such asyield, disease resistance, pest resistance, and plant performance inextreme weather conditions.

Progeny of variety XB02C03 may also be characterized through theirfilial relationship with soybean variety XB02C03, as, for example, beingwithin certain number of breeding crosses of soybean variety XB02C03. Abreeding cross is a cross made to introduce new genetics into theprogeny, and is distinguished from a cross, such as a self or a sibcross, made to select among existing genetic alleles. The lower thenumber of breeding crosses in the pedigree, the closer the relationshipbetween soybean variety XB02C03 and its progeny. For example, progenyproduced by the methods described herein may be within 1, 2, 3, 4 or 5breeding crosses of soybean variety XB02C03.

A soybean variety needs to be homogeneous, substantially homozygous andreproducible to be useful as a commercial variety. There are manyanalytical methods available to determine the homozygotic stability,phenotypic stability, and identity of these varieties.

The oldest and most traditional method of analysis is the observation ofphenotypic traits. The data is usually collected in field experimentsover the life of the soybean plants to be examined. Phenotypiccharacteristics most often observed are for traits associated with seedyield, seed protein and oil content, lodging resistance, diseaseresistance, maturity, plant height, shattering resistance, etc.

In addition to phenotypic observations, the genotype of a plant can alsobe examined. There are many laboratory-based techniques available forthe analysis, comparison and characterization of plant genotype; amongthese are Isozyme Electrophoresis, Restriction Fragment LengthPolymorphisms (RFLPs), Randomly Amplified Polymorphic DNAs (RAPDs),Arbitrarily Primed Polymerase Chain Reaction (AP-PCR), DNA AmplificationFingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs),Amplified Fragment Length Polymorphisms (AFLPs), Simple Sequence Repeats(SSRS) which are also referred to as Microsatellites, and SingleNucleotide Polymorphisms (SNPs).

Isozyme Electrophoresis and RFLPs have been widely used to determinegenetic composition. Shoemaker and Olsen, ((1993) Molecular Linkage Mapof Soybean (Glycine max L. Merr.). p. 6.131-6.138. In S. J. O'Brien(ed.) Genetic Maps: Locus Maps of Complex Genomes. Cold Spring HarborLaboratory Press. Cold Spring Harbor, N.Y.), developed a moleculargenetic linkage map that consisted of 25 linkage groups with about 365RFLP, 11 RAPD (random amplified polymorphic DNA), three classicalmarkers, and four isozyme loci. See also, Shoemaker R. C. 1994 RFLP Mapof Soybean. P. 299-309 In R. L. Phillips and I. K. Vasil (ed.) DNA-basedmarkers in plants. Kluwer Academic Press Dordrecht, the Netherlands.

SSR technology is currently the most efficient and practical markertechnology; more marker loci can be routinely used and more alleles permarker locus can be found using SSRs in comparison to RFLPs. For exampleDiwan and Cregan, described a highly polymorphic microsatellite loci inSoybean with as many as 26 alleles. (Diwan, N., and P. B. Cregan 1997Automated sizing of fluorescent-labeled simple sequence repeat (SSR)markers to assay genetic variation in Soybean Theor. Appl. Genet.95:220-225.) Single Nucleotide Polymorphisms may also be used toidentify the unique genetic composition of the invention and progenyvarieties retaining that unique genetic composition. Various molecularmarker techniques may be used in combination to enhance overallresolution.

Soybean DNA molecular marker linkage maps have been rapidly constructedand widely implemented in genetic studies. One such study is describedin Cregan et. al, “An Integrated Genetic Linkage Map of the SoybeanGenome” Crop Science 39:1464-1490 (1999). Sequences and PCR conditionsof SSR Loci in Soybean as well as the most current genetic map may belocated at the world wide web soybase.agron.iastate.edu or atsoybase.ncgr.org the disclosures of which are incorporated herein byreference.

Mutation breeding is another method of introducing new traits intosoybean variety XB02C03. Mutations that occur spontaneously or areartificially induced can be useful sources of variability for a plantbreeder. The goal of artificial mutagenesis is to increase the rate ofmutation for a desired characteristic. Mutation rates can be increasedby many different means including temperature, long-term seed storage,tissue culture conditions, radiation; such as X-rays, Gamma rays (e.g.cobalt 60 or cesium 137), neutrons, (product of nuclear fission byuranium 235 in an atomic reactor), Beta radiation (emitted fromradioisotopes such as phosphorus 32 or carbon 14), or ultravioletradiation (preferably from 2500 to 2900 nm), or chemical mutagens (suchas base analogues (5-bromo-uracil), related compounds (8-ethoxycaffeine), antibiotics (streptonigrin), alkylating agents (sulfurmustards, nitrogen mustards, epoxides, ethylenamines, sulfates,sulfonates, sulfones, lactones), azide, hydroxylamine, nitrous acid, oracridines. Once a desired trait is observed through mutagenesis thetrait may then be incorporated into existing germplasm by traditionalbreeding techniques. Details of mutation breeding can be found in“Principals of Cultivar Development” Fehr, 1993 Macmillan PublishingCompany the disclosure of which is incorporated herein by reference. Theproduction of double haploids can also be used for the development ofhomozygous varieties in the breeding program. Double haploids areproduced by the doubling of a set of chromosomes (1N) from aheterozygous plant to produce a completely homozygous individual. Forexample. See Wan et al., “Efficient Production of Doubled Haploid PlantsThrough Colchicine Treatment of Anther-Derived Maize callus” Theoreticaland Applied genetics, 77:889-892, 1989. This can be advantageous becausethe process omits the generations of selfing needed to obtain ahomozygous plant from a heterozygous source.

This invention is also directed to the use of variety XB02C03 in tissueculture. Tissue culture of various tissues of soybeans and regenerationof plants therefrom is well known and widely published. For example,reference may be had to Komatsuda, T. et al., “Genotype X SucroseInteractions for Somatic Embryogenesis in Soybean,” Crop Sci. 31:333-337(1991); Stephens, P. A. et al., “Agronomic Evaluation ofTissue-Culture-Derived Soybean Plants,” Theor. Appl. Genet. (1991)82:633-635; Komatsuda, T. et al., “Maturation and Germination of SomaticEmbryos as Affected by Sucrose and Plant Growth Regulators in SoybeansGlycine gracilis Skvortz and Glycine max (L.) Merr.,” Plant Cell, Tissueand Organ Culture, 28:103-113 (1992); Dhir, S. et al., “Regeneration ofFertile Plants from Protoplasts of Soybean (Glycine max L. Merr.):Genotypic Differences in Culture Response,” Plant Cell Reports (1992)11:285-289; Pandey, P. et al., “Plant Regeneration from Leaf andHypocotyl Explants of Glycine wightii (W. and A.) VERDC. var.longicauda,” Japan J. Breed. 42:1-5 (1992); and Shetty, K., et al.,“Stimulation of In Vitro Shoot Organogenesis in Glycine max (Merrill.)by Allantoin and Amides,” Plant Science 81:(1992) 245-251; as well asU.S. Pat. No. 5,024,944, issued Jun. 18, 1991 to Collins et al. and U.S.Pat. 5,008,200, issued Apr. 16, 1991 to Ranch et al., the disclosures ofwhich are hereby incorporated herein in their entirety by reference.Thus, another aspect of this invention is to provide cells which upongrowth and differentiation produce soybean plants having thephysiological and morphological characteristics of soybean varietyXB02C03.

Applicant(s) have made a deposit of at least 2500 seeds of SoybeanVariety XB02C03 with the American Type Culture Collection (ATCC),Manassas, Va. 20110 USA, ATCC Deposit No. PTA-5765. The seeds depositedwith the ATCC on Jan. 15, 2004 were taken from the deposit maintained byPioneer Hi-Bred Intemational, Inc., 800 Capital Square,. 400 LocustStreet, Des Moines, Iowa 50309-2340 since prior to the filing date ofthis application. Access to this deposit will be available during thependency of the application to the Commissioner of Patents andTrademarks and persons determined by the Commissioner to be entitledthereto upon request. Upon allowance of any claims in the application,the Applicant(s) will make the deposit available to the public pursuantto 37 CFR 1.808. This deposit of Soybean Variety XB02C03 will bemaintained in the ATCC depository, which is a public depository, for aperiod of 30 years, or 5 years after the most recent request, or for theenforceable life of the patent, whichever is longer, and will bereplaced if it becomes nonviable during that period. Additionally,Applicant(s) have or will satisfy all the requirements of 37 C.F.R§§1.801-1.809, including providing an indication of the viability of thesample upon deposit. Applicant(s) have no authority to waive anyrestrictions imposed by law on the transfer of biological material orits transportation in commerce. Applicant(s) do not waive anyinfringement of their rights granted under this patent or under thePlant Variety Protection Act (7 USC 2321 et seq.) U.S. Plant VarietyProtection of Soybean Variety XB02C03 has been applied for underapplication Ser. No. 200400088.

All publications, patents and patent applications mentioned in thespecification are indicative of the level of those skilled in the art towhich this invention pertains. All such publications, patents and patentapplications are incorporated by reference herein to the same extent asif each was specifically and individually indicated to be incorporatedby reference herein.

The foregoing invention has been described in detail by way ofillustration and example for purposes of clarity and understanding.However, it will be obvious that certain changes and modifications suchas backcross conversions, mutations, somoclonal variants, variantindividuals selected from large populations of the plants of the instantvariety and the like may be practiced within the scope of the invention.

What is claimed is:
 1. A soybean seed of soybean variety XB02C03,representative seed of said soybean variety XB02C03 having beendeposited under ATCC Accession No. PTA-5765.
 2. A soybean plant, or apart thereof, produced by growing the seed of claim
 1. 3. The soybeanplant part of claim 2 wherein said part is pollen.
 4. The soybean plantpart of claim 2 wherein said part is an ovule.
 5. A tissue culture ofprotoplasts or regenerable cells from the plant of claim
 2. 6. Thetissue culture according to claim 5, the cells or protoplasts of thetissue culture are obtained from a plant tissues selected from the groupconsisting of: leaf, pollen, cotyledon, hypocotyl, embryos, root, pod,flower, shoot and stalk.
 7. A soybean plant regenerated from the tissueculture of claim 5, having all the morphological and physiologicalcharacteristics of soybean variety XB02C03, representative seed of saidsoybean variety XB02C03 having been deposited under ATCC Accession No.PTA-5765.
 8. A method for producing a progeny soybean plant comprisingcrossing the plant of claim 2 with a second soybean plant, harvestingthe resultant soybean seed, and growing a progeny soybean plant.